The present invention relates to combining heat or cold therapy with magnet therapy. Application of heat therapy is a standard practice in medicine for the treatment of common ailments such as arthritis, bursitis, headache, back and neck pain, menstrual cramps, fibromyalgia and muscle soreness. Likewise cold therapy is a standard practice in medicine for the treatment of strains, sprains, headache and muscle spasms.
Medical professionals generally recommend cold therapy during the first 24 to 48 hours after the "acute" phase of an injury such as a strain or sprain. During this time, the blood vessels around the injured tissues open up, rushing blood, nutrients and fluids to the area to help the tissues heal. A problem is that the increased blood flow often causes the healthy tissues surrounding the injury to swell and become inflamed. If swelling and inflammation are not stopped or slowed, more extensive tissue damage may occur and the injury may take longer to heal. The additional fluids in the swollen tissues may press on nerves around the injury site, increasing pain. Cold therapy reduces swelling and inflammation in a number of ways: it lowers the skin temperature, which helps to constrict the blood vessels; it slows the metabolic rate of the injured tissues; and it slows the body's release of chemicals that dilate the blood vessels, further helping to reduce blood flow to the area. Cold therapy also numbs the injured area and reduces muscle spasms, both of which help to relieve pain.
Heat therapy is medically recommended for treatment to an injury after the swelling and inflammation subside, generally after the first 24-48 hours. Heat therapy increases skin temperature, causing blood vessels to dilate and increases blood flow to the area. The increased blood flow and nutrients help to nourish injured tissues. Heat also can relieve muscle spasms and pain triggered by loss of blood flow to the area, and increases the elasticity of the connective tissue of collagen, helping to decrease joint stiffness. Heat therapy is especially helpful in the treatment of tom muscles and tendons after the inflammation and swelling have gone down. Most medical textbooks recommend moist heat over dry heat due to moist heat's ability to penetrate deeper into the tissue thereby increasing blood flow, however it is not always convenient to use moist heat as it dampens clothing, bedding and furniture. See, Lehmann, Therapeutic Heat and Cold, pp. 440 (3rd edition, 1987).
Magnet therapy has been shown to assist in healing injuries. Researchers at Baylor University College of Medicine, Vanderbilt University Medical Center, Tufts University School of Medicine, Mount Sinai Medical Center and New York Medical College at Valhalla and others have published reports demonstrating the effectiveness of magnets in increasing blood flow, reducing pain from sports injuries, relieving pain from fibromyalgia, increasing collagen, reducing muscle spasms and decreasing joint stiffness. F. Wunsch-Binder of the Department of Radiology, University of Kiel Medical School, Germany, conducted a study called "The Influence of Static Magnetic Fields on Skin Temperature and Blood Flow in Man." He found that human skin undergoes temperature change within a static magnetic field. Temperature variations increased from 0.3 degrees centigrade to 5 degrees centigrade. It was assumed that the increase in temperature was caused by increase in blood flow.
William H. Phillpott, MD published his research on magnetic therapy in 1990, Phillpott and Taplin Biomagnetic Handbook (1990). His research indicates that magnets can reduce edema if the magnet is placed several inches to the side of an injury in order to pull fluids toward the positive field and away from the site of swelling. Phillpott suggests that magnets can increase cellular oxygenation and speed healing.
In a study conducted by Mount Sinai Medical Center, New York, to determine the effect of cell/tissue repair and regeneration, magnetic device patches were placed over wounds for a total of 48 hours. The results suggest that in approximately 60% of patients' pain, edema and discoloration were diminished, and in 75% of patients pain and edema disappeared.
The present invention allows the user to choose to apply moist heat or dry heat therapy, with or without magnet therapy, thus receiving the benefits of all three treatment modalities.
Multi-purpose moist heat-cold packs have been in use for several years. For example U.S. Pat No 5,447,531 to Wood and U.S. Pat No. 5,391,198 to Cheney illustrates such packs. However these type packs have several limitations. Both of these inventions use fabric for the envelope containing the superabsorbent polyacrylamide filler, however fabric is not a good conductor of cold, as the fabric acts as an insulation barrier between the filler and the skin, limiting appropriate cold application to approximately 10 minutes. Since most medical textbooks recommend cold therapy application of 48 degrees F. for 20 minutes these packs cannot deliver the medically recommended range of cold therapy. (Lehman, supra @ pp. 401-405) Also, the above referenced patents call for a water permeable membrane on both sides of the pack, which limits the pack to moist heat therapy. Also, Cheney teaches placing the pack in a refrigerator or freezer. As the interior filler contains no antifreeze properties, this pack would freeze solid if placed in the freezer, and thus not be pliable. Cheney teaches that the pack would be 21.4 degrees F. after 25 minutes out of a freezer. This pack and all other packs that require freezing would subject the patient to frostbite or skin damage, as 48 degrees F. as referenced by Lehman is the medically recommended range of cold therapy. Application of a pack such as Cheney teaches would could cause frostbite or skin damage to diabetics, children or individuals with poor circulation or decreased sensory perception. Also, a frozen pack such as Cheney teaches would be subject to causing a rip or tear in the fabric, due to the solid ice formation of the interior filler. Cheney further teaches the use of a synthetic fabric such as that sold under the trademark SONTARA by Dupont or other similar fabrics. Wood teaches a synthetic fabric such as NYLON coated with thin polyurethane. As SONTARA and NYLON are synthetic fabrics they and are both hydrophobic. Wood teaches the inclusion of cotton wicking material sewn into the pack to facilitate hydration of the polyacrylamide.
An advantage of the present invention is that the water permeable side of the pack utilizes the patented process (U.S. Pat. No. 5,855,623) of grafting of a hydrophilic molecule to the surface of the fiber which reduces the hydration time by approximately one half over Cheney and Wood. A hydrophilic fiber such as INTERA can be purchased from the INTERA Corporation, Chattanooga, TENN. The polyacrylamide-type packs taught by Wood and Cheney are also subject to mold, mildew and fungal and bacteria growth, as the surface material stays moist for days or weeks when not in use, providing an ideal environment for the growth of microorganisms. Another advantage of the INTERA fabric is that it reduces bacteria, mold, mildew and odors from forming on the pack, as the surface of the pack dries before microorganisms can replicate. Another advantage of using the INTERA fabric is that it is more soil resistant and easier to clean than SONTARA or NYLON. Another advantage over INTERA over fabrics taught in Wood and Cheney is that it improves the delivery of cold therapy due to the increased rate of evaporation of the water on the fabric surface, thus allowing evaporative cooling. Wood teaches the coating of the NYLON fabric with polyurethane to prevent the escape of polyacrylamide through the fabric weaves. Cheney does not refer to the escape of the polymer from the cavity. However, in actual use this is a major problem for both of these methods of construction. Over time and use the polyacrylamide breaks down into very small particles, which escape through the fabric, thus causing a slick and tacky surface. This is particularly true of the Cheney construction as no method of containment of the small particle polyacrylamide is provided. A polyether or ester foam laminated to the INTERA fabric has been found to improve the restriction of the seepage of the polyacrylamide molecules, due to the complex pore structure of the foam, and the ability of INTERA fabric to rapidly dehydrate any polyacrylamide which reaches the surface, thus eliminating any slick or tacky feel.
U.S. Pat. No. 5,179,944 issued to McSymytx teaches the application of moist heat, dry heat or cold to a patient, however this invention requires the user to place the pack in a separate cover for the delivery of dry heat, which is not necessary with the present invention. McSymytx also teaches filler material comprised of sand, which is expensive to ship and store, and would not easily conform to areas of the body such as wrists, knees or ankles. McSymytx also teaches cooling by freezer, thus bringing the application temperature below 32 degrees F. which is uncomfortable at best and could cause frostbite and skin damage the same as previously mentioned in Cheney. In addition McSymytx teaches a fabric exterior, which creates an insulation barrier between the skin and pack as Cheney and Wood, reducing the cold delivery time to about 10 minutes. Since the pack taught by McSymytx is conditioned by water and enclosed in fabric, it provides the same environment as Cheney and Wood for the growth of microorganisms on the surface of the pack.
U.S. Pat. No. 4,177,796 to Franco-Vila was granted teaching the incorporation of magnet and heat therapy in a vibrating device. The Franco-Vila patent is restricted to dry heat, vibration and magnetism. It also requires an AC power supply, and a teaches combination of electromagnets and permanent magnets. The present invention is an improvement over Franco-Vila in that it much less expensive to manufacture and therefore less expensive to the patient; is multi-purpose in that it allows application of any combination of magnets and dry heat, moist heat or cold therapy. The present invention is an improvement over Franco-Vila in that it does not require a power source for operation and allows application to areas of the body where a vibrating device is not appropriate such as the eyes. The present invention is a further improvement in that it allows several magnets to be grouped together for deeper penetration or spaced apart for a more wide spread therapeutic effect.